Hammocks have been known for many, many years, and have been widely used for both recreational and utilitarian purpose. Because of the recreational popularity of hammocks, numerous types of foldable hammock supporting structures for holding the hammock in an outstretched position have been suggested. However, such foldable or collapsible hammock supports are typically complex in construction and are generally heavy and quite bulky when in a collapsed or folded configuration. Accordingly, they are extremely difficult to transport from place to place.
One prior art collapsible hammock is described in U.S. Pat. No. 5,983,422 (refer to FIG. 9). Although it is lightweight in construction, and easy to use, it not suitable for heavy people. The stop pin 58 may be not strong enough to prevent two support arms 50 from rotating inwardly. It would cause the stretched hammock to collapse under the weight of a heavy user. So a risk of safety exists. From this consideration the designers should pay more attention to the problem of making a foldable hammock stronger for supporting heavier person's weight.
It will become more apparent from the discussion that the many efforts should be focused on strengthening the force to resist the inward rotation of two support arms 50, thereby maintaining the rigidity of stretched position of the hammock when a heavier person's weight exerts against the hammock surface.